2D AND 3D
In the 18th century 'candle silhouettes' were a popular form of portraiture because they could be drawn in one sitting and were therefor affordable. A single candle was used to cast a shadow of the sitter's profile in silhouette.
I used this method of single source light to sketch the silhouettes of some writers and artists at the Vermont Studio Center.
The God Janus is depicted with two faces, to look to the future and to the past simultaneously.